Megastigmatrienone (3,5,5-trimethyl-4-(2-butenylidene)-cyclohex-2-en-1-one, as a mixture of isomers) 1 is a component of Burley as well as Turkish and Greek tobaccos (See D. L. Roberts and W. A. Rhode, Tobacco Science, 1972, 16, 107; E. Demole and D. Berthet, Helv. Chim. Acta, 1972, 55, 1866; A. J. Aasen, B. Kimland, S. Almqvist and C. R. Enzell, Acta. Chem. Scand., 1972, 26, 2573; and J. W. Schumacher and L. Vestal, Tobacco Science, 1974, 43) and is known to make an important contribution to the overall flavor character of tobacco. ##STR1##
Megastigmatrienone 1 can be considered a dehydration product of 3-oxo-.alpha.-ionol 2, also a constituent of tobacco (see A. J. Aasen, B. Kimland and C. R. Enzell, Acta Chem. Scand., 1971, 25, 1481). Glycosidyl derivatives of 2 have been described as useful smoke flavoring compositions (see R. C. Anderson, D. M. Gunn and J. A. Andrew, Ger. Offen. 2,634,304). Recently, R. Kaiser (Eur. Pat. Appl. 175, 251) has disclosed various esters of oxo-ionols of formula 3 as useful tobacco flavorants. ##STR2## R is C.sub.1 -C.sub.18 alkyl; Z is oxo and indicates a single or double bond.
A problem associated with the use of megastigmatrienone 1, however, is its tendency to polymerize making it difficult to store, transport and formulate.